If you saw people smiling when they mailed their tax returns , you can be sure that they're getting refunds! In fact, in 1987, 75 percent of all taxpayers were whistling "I'm in the money" on April 15. For many of us, a tax refund is an open invitation to spend recklessly. But, if you use it wisely, a refund can go a long way toward improving your financial fitness. Here are some tips from the New Jersey Society of Certified Public Accountants on how to make your refund dollars count: Wipe Out Bills: Think about this: The average American owes $1,600 in dept on credit cards. At 19 percent interest, that level of dept can cost up to $304 a year. To make matters worse, only 20 percent of the interest is tax deductible in 1989. If you have oustanding debt on your credit cards, why not use your refund to pay off all or part of your credit card bills?